Coverage Report

Created: 2025-07-01 06:54

/work/mbedtls-2.28.8/library/pkcs5.c
Line
Count
Source (jump to first uncovered line)
1
/**
2
 * \file pkcs5.c
3
 *
4
 * \brief PKCS#5 functions
5
 *
6
 * \author Mathias Olsson <mathias@kompetensum.com>
7
 *
8
 *  Copyright The Mbed TLS Contributors
9
 *  SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
10
 */
11
/*
12
 * PKCS#5 includes PBKDF2 and more
13
 *
14
 * http://tools.ietf.org/html/rfc2898 (Specification)
15
 * http://tools.ietf.org/html/rfc6070 (Test vectors)
16
 */
17
18
#include "common.h"
19
20
#if defined(MBEDTLS_PKCS5_C)
21
22
#include "mbedtls/pkcs5.h"
23
#include "mbedtls/error.h"
24
25
#if defined(MBEDTLS_ASN1_PARSE_C)
26
#include "mbedtls/asn1.h"
27
#include "mbedtls/cipher.h"
28
#include "mbedtls/oid.h"
29
#endif /* MBEDTLS_ASN1_PARSE_C */
30
31
#include <string.h>
32
33
#include "mbedtls/platform.h"
34
35
36
#if defined(MBEDTLS_ASN1_PARSE_C)
37
static int pkcs5_parse_pbkdf2_params(const mbedtls_asn1_buf *params,
38
                                     mbedtls_asn1_buf *salt, int *iterations,
39
                                     int *keylen, mbedtls_md_type_t *md_type)
40
0
{
41
0
    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
42
0
    mbedtls_asn1_buf prf_alg_oid;
43
0
    unsigned char *p = params->p;
44
0
    const unsigned char *end = params->p + params->len;
45
46
0
    if (params->tag != (MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE)) {
47
0
        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PKCS5_INVALID_FORMAT,
48
0
                                 MBEDTLS_ERR_ASN1_UNEXPECTED_TAG);
49
0
    }
50
    /*
51
     *  PBKDF2-params ::= SEQUENCE {
52
     *    salt              OCTET STRING,
53
     *    iterationCount    INTEGER,
54
     *    keyLength         INTEGER OPTIONAL
55
     *    prf               AlgorithmIdentifier DEFAULT algid-hmacWithSHA1
56
     *  }
57
     *
58
     */
59
0
    if ((ret = mbedtls_asn1_get_tag(&p, end, &salt->len,
60
0
                                    MBEDTLS_ASN1_OCTET_STRING)) != 0) {
61
0
        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PKCS5_INVALID_FORMAT, ret);
62
0
    }
63
64
0
    salt->p = p;
65
0
    p += salt->len;
66
67
0
    if ((ret = mbedtls_asn1_get_int(&p, end, iterations)) != 0) {
68
0
        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PKCS5_INVALID_FORMAT, ret);
69
0
    }
70
71
0
    if (p == end) {
72
0
        return 0;
73
0
    }
74
75
0
    if ((ret = mbedtls_asn1_get_int(&p, end, keylen)) != 0) {
76
0
        if (ret != MBEDTLS_ERR_ASN1_UNEXPECTED_TAG) {
77
0
            return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PKCS5_INVALID_FORMAT, ret);
78
0
        }
79
0
    }
80
81
0
    if (p == end) {
82
0
        return 0;
83
0
    }
84
85
0
    if ((ret = mbedtls_asn1_get_alg_null(&p, end, &prf_alg_oid)) != 0) {
86
0
        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PKCS5_INVALID_FORMAT, ret);
87
0
    }
88
89
0
    if (mbedtls_oid_get_md_hmac(&prf_alg_oid, md_type) != 0) {
90
0
        return MBEDTLS_ERR_PKCS5_FEATURE_UNAVAILABLE;
91
0
    }
92
93
0
    if (p != end) {
94
0
        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PKCS5_INVALID_FORMAT,
95
0
                                 MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
96
0
    }
97
98
0
    return 0;
99
0
}
100
101
#if !defined(MBEDTLS_CIPHER_PADDING_PKCS7)
102
int mbedtls_pkcs5_pbes2_ext(const mbedtls_asn1_buf *pbe_params, int mode,
103
                            const unsigned char *pwd,  size_t pwdlen,
104
                            const unsigned char *data, size_t datalen,
105
                            unsigned char *output, size_t output_size,
106
                            size_t *output_len);
107
#endif
108
109
int mbedtls_pkcs5_pbes2(const mbedtls_asn1_buf *pbe_params, int mode,
110
                        const unsigned char *pwd,  size_t pwdlen,
111
                        const unsigned char *data, size_t datalen,
112
                        unsigned char *output)
113
0
{
114
0
    size_t output_len = 0;
115
116
    /* We assume caller of the function is providing a big enough output buffer
117
     * so we pass output_size as SIZE_MAX to pass checks, However, no guarantees
118
     * for the output size actually being correct.
119
     */
120
0
    return mbedtls_pkcs5_pbes2_ext(pbe_params, mode, pwd, pwdlen, data,
121
0
                                   datalen, output, SIZE_MAX, &output_len);
122
0
}
123
124
int mbedtls_pkcs5_pbes2_ext(const mbedtls_asn1_buf *pbe_params, int mode,
125
                            const unsigned char *pwd,  size_t pwdlen,
126
                            const unsigned char *data, size_t datalen,
127
                            unsigned char *output, size_t output_size,
128
                            size_t *output_len)
129
0
{
130
0
    int ret, iterations = 0, keylen = 0;
131
0
    unsigned char *p, *end;
132
0
    mbedtls_asn1_buf kdf_alg_oid, enc_scheme_oid, kdf_alg_params, enc_scheme_params;
133
0
    mbedtls_asn1_buf salt;
134
0
    mbedtls_md_type_t md_type = MBEDTLS_MD_SHA1;
135
0
    unsigned char key[32], iv[32];
136
0
    const mbedtls_md_info_t *md_info;
137
0
    const mbedtls_cipher_info_t *cipher_info;
138
0
    mbedtls_md_context_t md_ctx;
139
0
    mbedtls_cipher_type_t cipher_alg;
140
0
    mbedtls_cipher_context_t cipher_ctx;
141
0
    unsigned int padlen = 0;
142
143
0
    p = pbe_params->p;
144
0
    end = p + pbe_params->len;
145
146
    /*
147
     *  PBES2-params ::= SEQUENCE {
148
     *    keyDerivationFunc AlgorithmIdentifier {{PBES2-KDFs}},
149
     *    encryptionScheme AlgorithmIdentifier {{PBES2-Encs}}
150
     *  }
151
     */
152
0
    if (pbe_params->tag != (MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE)) {
153
0
        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PKCS5_INVALID_FORMAT,
154
0
                                 MBEDTLS_ERR_ASN1_UNEXPECTED_TAG);
155
0
    }
156
157
0
    if ((ret = mbedtls_asn1_get_alg(&p, end, &kdf_alg_oid,
158
0
                                    &kdf_alg_params)) != 0) {
159
0
        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PKCS5_INVALID_FORMAT, ret);
160
0
    }
161
162
    // Only PBKDF2 supported at the moment
163
    //
164
0
    if (MBEDTLS_OID_CMP(MBEDTLS_OID_PKCS5_PBKDF2, &kdf_alg_oid) != 0) {
165
0
        return MBEDTLS_ERR_PKCS5_FEATURE_UNAVAILABLE;
166
0
    }
167
168
0
    if ((ret = pkcs5_parse_pbkdf2_params(&kdf_alg_params,
169
0
                                         &salt, &iterations, &keylen,
170
0
                                         &md_type)) != 0) {
171
0
        return ret;
172
0
    }
173
174
0
    md_info = mbedtls_md_info_from_type(md_type);
175
0
    if (md_info == NULL) {
176
0
        return MBEDTLS_ERR_PKCS5_FEATURE_UNAVAILABLE;
177
0
    }
178
179
0
    if ((ret = mbedtls_asn1_get_alg(&p, end, &enc_scheme_oid,
180
0
                                    &enc_scheme_params)) != 0) {
181
0
        return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PKCS5_INVALID_FORMAT, ret);
182
0
    }
183
184
0
    if (mbedtls_oid_get_cipher_alg(&enc_scheme_oid, &cipher_alg) != 0) {
185
0
        return MBEDTLS_ERR_PKCS5_FEATURE_UNAVAILABLE;
186
0
    }
187
188
0
    cipher_info = mbedtls_cipher_info_from_type(cipher_alg);
189
0
    if (cipher_info == NULL) {
190
0
        return MBEDTLS_ERR_PKCS5_FEATURE_UNAVAILABLE;
191
0
    }
192
193
    /*
194
     * The value of keylen from pkcs5_parse_pbkdf2_params() is ignored
195
     * since it is optional and we don't know if it was set or not
196
     */
197
0
    keylen = cipher_info->key_bitlen / 8;
198
199
0
    if (enc_scheme_params.tag != MBEDTLS_ASN1_OCTET_STRING ||
200
0
        enc_scheme_params.len != cipher_info->iv_size) {
201
0
        return MBEDTLS_ERR_PKCS5_INVALID_FORMAT;
202
0
    }
203
204
0
    if (mode == MBEDTLS_PKCS5_DECRYPT) {
205
0
        if (output_size < datalen) {
206
0
            return MBEDTLS_ERR_ASN1_BUF_TOO_SMALL;
207
0
        }
208
0
    }
209
210
0
    if (mode == MBEDTLS_PKCS5_ENCRYPT) {
211
0
        padlen = cipher_info->block_size - (datalen % cipher_info->block_size);
212
0
        if (output_size < (datalen + padlen)) {
213
0
            return MBEDTLS_ERR_ASN1_BUF_TOO_SMALL;
214
0
        }
215
0
    }
216
217
0
    mbedtls_md_init(&md_ctx);
218
219
0
    mbedtls_cipher_init(&cipher_ctx);
220
221
0
    memcpy(iv, enc_scheme_params.p, enc_scheme_params.len);
222
223
0
    if ((ret = mbedtls_md_setup(&md_ctx, md_info, 1)) != 0) {
224
0
        goto exit;
225
0
    }
226
227
0
    if ((ret = mbedtls_pkcs5_pbkdf2_hmac(&md_ctx, pwd, pwdlen, salt.p, salt.len,
228
0
                                         iterations, keylen, key)) != 0) {
229
0
        goto exit;
230
0
    }
231
232
0
    if ((ret = mbedtls_cipher_setup(&cipher_ctx, cipher_info)) != 0) {
233
0
        goto exit;
234
0
    }
235
236
0
    if ((ret = mbedtls_cipher_setkey(&cipher_ctx, key, 8 * keylen,
237
0
                                     (mbedtls_operation_t) mode)) != 0) {
238
0
        goto exit;
239
0
    }
240
241
0
#if defined(MBEDTLS_CIPHER_MODE_WITH_PADDING)
242
0
    {
243
        /* PKCS5 uses CBC with PKCS7 padding (which is the same as
244
         * "PKCS5 padding" except that it's typically only called PKCS5
245
         * with 64-bit-block ciphers).
246
         */
247
0
        mbedtls_cipher_padding_t padding = MBEDTLS_PADDING_PKCS7;
248
#if !defined(MBEDTLS_CIPHER_PADDING_PKCS7)
249
        /* For historical reasons, when decrypting, this function works when
250
         * decrypting even when support for PKCS7 padding is disabled. In this
251
         * case, it ignores the padding, and so will never report a
252
         * password mismatch.
253
         */
254
        if (mode == MBEDTLS_DECRYPT) {
255
            padding = MBEDTLS_PADDING_NONE;
256
        }
257
#endif
258
0
        if ((ret = mbedtls_cipher_set_padding_mode(&cipher_ctx, padding)) != 0) {
259
0
            goto exit;
260
0
        }
261
0
    }
262
0
#endif /* MBEDTLS_CIPHER_MODE_WITH_PADDING */
263
0
    if ((ret = mbedtls_cipher_crypt(&cipher_ctx, iv, enc_scheme_params.len,
264
0
                                    data, datalen, output, output_len)) != 0) {
265
0
        ret = MBEDTLS_ERR_PKCS5_PASSWORD_MISMATCH;
266
0
    }
267
268
0
exit:
269
0
    mbedtls_md_free(&md_ctx);
270
0
    mbedtls_cipher_free(&cipher_ctx);
271
272
0
    return ret;
273
0
}
274
#endif /* MBEDTLS_ASN1_PARSE_C */
275
276
int mbedtls_pkcs5_pbkdf2_hmac(mbedtls_md_context_t *ctx,
277
                              const unsigned char *password,
278
                              size_t plen, const unsigned char *salt, size_t slen,
279
                              unsigned int iteration_count,
280
                              uint32_t key_length, unsigned char *output)
281
0
{
282
0
    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
283
0
    int j;
284
0
    unsigned int i;
285
0
    unsigned char md1[MBEDTLS_MD_MAX_SIZE];
286
0
    unsigned char work[MBEDTLS_MD_MAX_SIZE];
287
0
    unsigned char md_size = mbedtls_md_get_size(ctx->md_info);
288
0
    size_t use_len;
289
0
    unsigned char *out_p = output;
290
0
    unsigned char counter[4];
291
292
0
    memset(counter, 0, 4);
293
0
    counter[3] = 1;
294
295
#if UINT_MAX > 0xFFFFFFFF
296
    if (iteration_count > 0xFFFFFFFF) {
297
        return MBEDTLS_ERR_PKCS5_BAD_INPUT_DATA;
298
    }
299
#endif
300
301
0
    if ((ret = mbedtls_md_hmac_starts(ctx, password, plen)) != 0) {
302
0
        return ret;
303
0
    }
304
0
    while (key_length) {
305
        // U1 ends up in work
306
        //
307
0
        if ((ret = mbedtls_md_hmac_update(ctx, salt, slen)) != 0) {
308
0
            goto cleanup;
309
0
        }
310
311
0
        if ((ret = mbedtls_md_hmac_update(ctx, counter, 4)) != 0) {
312
0
            goto cleanup;
313
0
        }
314
315
0
        if ((ret = mbedtls_md_hmac_finish(ctx, work)) != 0) {
316
0
            goto cleanup;
317
0
        }
318
319
0
        if ((ret = mbedtls_md_hmac_reset(ctx)) != 0) {
320
0
            goto cleanup;
321
0
        }
322
323
0
        memcpy(md1, work, md_size);
324
325
0
        for (i = 1; i < iteration_count; i++) {
326
            // U2 ends up in md1
327
            //
328
0
            if ((ret = mbedtls_md_hmac_update(ctx, md1, md_size)) != 0) {
329
0
                goto cleanup;
330
0
            }
331
332
0
            if ((ret = mbedtls_md_hmac_finish(ctx, md1)) != 0) {
333
0
                goto cleanup;
334
0
            }
335
336
0
            if ((ret = mbedtls_md_hmac_reset(ctx)) != 0) {
337
0
                goto cleanup;
338
0
            }
339
340
            // U1 xor U2
341
            //
342
0
            for (j = 0; j < md_size; j++) {
343
0
                work[j] ^= md1[j];
344
0
            }
345
0
        }
346
347
0
        use_len = (key_length < md_size) ? key_length : md_size;
348
0
        memcpy(out_p, work, use_len);
349
350
0
        key_length -= (uint32_t) use_len;
351
0
        out_p += use_len;
352
353
0
        for (i = 4; i > 0; i--) {
354
0
            if (++counter[i - 1] != 0) {
355
0
                break;
356
0
            }
357
0
        }
358
0
    }
359
360
0
cleanup:
361
    /* Zeroise buffers to clear sensitive data from memory. */
362
0
    mbedtls_platform_zeroize(work, MBEDTLS_MD_MAX_SIZE);
363
0
    mbedtls_platform_zeroize(md1, MBEDTLS_MD_MAX_SIZE);
364
365
0
    return ret;
366
0
}
367
368
#if defined(MBEDTLS_SELF_TEST)
369
370
#if !defined(MBEDTLS_SHA1_C)
371
int mbedtls_pkcs5_self_test(int verbose)
372
{
373
    if (verbose != 0) {
374
        mbedtls_printf("  PBKDF2 (SHA1): skipped\n\n");
375
    }
376
377
    return 0;
378
}
379
#else
380
381
0
#define MAX_TESTS   6
382
383
static const size_t plen_test_data[MAX_TESTS] =
384
{ 8, 8, 8, 24, 9 };
385
386
static const unsigned char password_test_data[MAX_TESTS][32] =
387
{
388
    "password",
389
    "password",
390
    "password",
391
    "passwordPASSWORDpassword",
392
    "pass\0word",
393
};
394
395
static const size_t slen_test_data[MAX_TESTS] =
396
{ 4, 4, 4, 36, 5 };
397
398
static const unsigned char salt_test_data[MAX_TESTS][40] =
399
{
400
    "salt",
401
    "salt",
402
    "salt",
403
    "saltSALTsaltSALTsaltSALTsaltSALTsalt",
404
    "sa\0lt",
405
};
406
407
static const uint32_t it_cnt_test_data[MAX_TESTS] =
408
{ 1, 2, 4096, 4096, 4096 };
409
410
static const uint32_t key_len_test_data[MAX_TESTS] =
411
{ 20, 20, 20, 25, 16 };
412
413
static const unsigned char result_key_test_data[MAX_TESTS][32] =
414
{
415
    { 0x0c, 0x60, 0xc8, 0x0f, 0x96, 0x1f, 0x0e, 0x71,
416
      0xf3, 0xa9, 0xb5, 0x24, 0xaf, 0x60, 0x12, 0x06,
417
      0x2f, 0xe0, 0x37, 0xa6 },
418
    { 0xea, 0x6c, 0x01, 0x4d, 0xc7, 0x2d, 0x6f, 0x8c,
419
      0xcd, 0x1e, 0xd9, 0x2a, 0xce, 0x1d, 0x41, 0xf0,
420
      0xd8, 0xde, 0x89, 0x57 },
421
    { 0x4b, 0x00, 0x79, 0x01, 0xb7, 0x65, 0x48, 0x9a,
422
      0xbe, 0xad, 0x49, 0xd9, 0x26, 0xf7, 0x21, 0xd0,
423
      0x65, 0xa4, 0x29, 0xc1 },
424
    { 0x3d, 0x2e, 0xec, 0x4f, 0xe4, 0x1c, 0x84, 0x9b,
425
      0x80, 0xc8, 0xd8, 0x36, 0x62, 0xc0, 0xe4, 0x4a,
426
      0x8b, 0x29, 0x1a, 0x96, 0x4c, 0xf2, 0xf0, 0x70,
427
      0x38 },
428
    { 0x56, 0xfa, 0x6a, 0xa7, 0x55, 0x48, 0x09, 0x9d,
429
      0xcc, 0x37, 0xd7, 0xf0, 0x34, 0x25, 0xe0, 0xc3 },
430
};
431
432
int mbedtls_pkcs5_self_test(int verbose)
433
0
{
434
0
    mbedtls_md_context_t sha1_ctx;
435
0
    const mbedtls_md_info_t *info_sha1;
436
0
    int ret, i;
437
0
    unsigned char key[64];
438
439
0
    mbedtls_md_init(&sha1_ctx);
440
441
0
    info_sha1 = mbedtls_md_info_from_type(MBEDTLS_MD_SHA1);
442
0
    if (info_sha1 == NULL) {
443
0
        ret = 1;
444
0
        goto exit;
445
0
    }
446
447
0
    if ((ret = mbedtls_md_setup(&sha1_ctx, info_sha1, 1)) != 0) {
448
0
        ret = 1;
449
0
        goto exit;
450
0
    }
451
452
0
    for (i = 0; i < MAX_TESTS; i++) {
453
0
        if (verbose != 0) {
454
0
            mbedtls_printf("  PBKDF2 (SHA1) #%d: ", i);
455
0
        }
456
457
0
        ret = mbedtls_pkcs5_pbkdf2_hmac(&sha1_ctx, password_test_data[i],
458
0
                                        plen_test_data[i], salt_test_data[i],
459
0
                                        slen_test_data[i], it_cnt_test_data[i],
460
0
                                        key_len_test_data[i], key);
461
0
        if (ret != 0 ||
462
0
            memcmp(result_key_test_data[i], key, key_len_test_data[i]) != 0) {
463
0
            if (verbose != 0) {
464
0
                mbedtls_printf("failed\n");
465
0
            }
466
467
0
            ret = 1;
468
0
            goto exit;
469
0
        }
470
471
0
        if (verbose != 0) {
472
0
            mbedtls_printf("passed\n");
473
0
        }
474
0
    }
475
476
0
    if (verbose != 0) {
477
0
        mbedtls_printf("\n");
478
0
    }
479
480
0
exit:
481
0
    mbedtls_md_free(&sha1_ctx);
482
483
0
    return ret;
484
0
}
485
#endif /* MBEDTLS_SHA1_C */
486
487
#endif /* MBEDTLS_SELF_TEST */
488
489
#endif /* MBEDTLS_PKCS5_C */